A few weeks ago, MACHINIST member Terence Addison posted a screenshot from RockAuto showing a bearing race with an outside diameter listed as:

2.688000000000000002 inches

Not 2.688.

Not 2.6880.

Not even 2.6880000001.

Nope.

Somewhere deep inside the internet, a computer decided machinists needed seventeen decimal places and then threw in an extra "2" at the end just to make sure everyone suffered equally.

The post reached more than 75,000 machinists and immediately turned into one of the funniest comment sections we've seen in a while.

As expected, the first group to show up were the guys who can apparently hold any tolerance known to mankind using equipment that belongs in a museum.

Patrick McClintock kicked things off:

Naturally, several machinists immediately agreed.

One guy claimed he used to do it with spring calipers and a 6-inch scale.

Another said he could hit it on a 60-year-old manual machine.

And at least three people suggested a hand file would be sufficient.

The internet remains undefeated.

Several commenters pointed out that achieving atomic-level precision doesn't actually require expensive equipment.

Apparently all you need is:

Brandon Bird Erhardt explained:

To which another machinist asked if the quill had wobble.

The response:

We're not sure that's an official metrology term, but everyone understood it immediately.

Every tolerance discussion eventually becomes a thermal expansion discussion.

This thread was no exception.

Several machinists pointed out that simply touching the part would probably change the dimension more than the entire tolerance shown on the screen.

One commenter noted:

Another suggested:

And perhaps the most accurate quality-control recommendation of the entire thread:

Fair question.

At this level, breathing near the part might qualify as a process change.

Then Jesse Guthritsch showed up and ruined everyone's joke by doing actual math.

According to Jesse:

In other words:

The tolerance wasn't merely impossible.

It was entering science-fiction territory.

One machinist referred to it as:

Another replied:

If your inspection report requires quantum mechanics, it may be time to revisit the print.

There were dozens of contenders.

But one comment stood above the rest.

Jay Murphy wrote:

Several machinists admitted they physically laughed out loud.

And honestly?

If you're filing warranty claims based on proton count, you've officially reached peak precision manufacturing.

Several commenters eventually pointed out the likely answer.

The dimension was probably entered as a decimal value that couldn't be represented perfectly by a computer. Instead of displaying a rounded number, the website simply spit out the full floating-point value.

In other words:

Nobody is machining wheel bearings to a quadrillionth of an inch.

At least we hope not.

Because at $3.66 each, that's one hell of a deal.

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